Brand new to KDE (mint gnome user for the previous 3 releases, ubuntu a few years prior to that).

I cant seem to move the panel widgets (specifically the tray and clock) to the right side. They started out there after install, but as soon as I added an application launch icon and moved it to the left, everything slid over and won't go back. When I drag the tray or clock to the right, they just snap back to the left side.

I've tried playing with the size of the panel and adding spacers, but no joy.

Try moving the the Task Manager to the left instead of moving the Clock to the right. I've noticed you need to be precise on hitting the area you need when you're at the end of the panel. And look for the shaded box to appear when you're on the right spot.